It is known to blend flexible coil polymers with liquid crystal polymers (LCPs) which are also termed "liquid crystalline polymers", the latter being either homopolymers or random copolymers. In such cases, the blends are formed by mixing the matrix and LCP additive under melt blending conditions for at least one of those components. Cogswell et al. in U.S. Pat. Nos. 4,386,174 and 4,438,236 advocate use of a temperature range over which the polymer capable of forming an anisotropic melt overlaps the temperature range over which the melt-processible polymer may be melt processed. (Also see Polymer Engineering and Science, Mid-September 1990, Vol. 30, No. 17, p. 1011). Isayev et al. in U.S. Pat. No. 4,728,698 indicates that mixing is to be carried out at a temperature at which both the base polymer and the LCP are melt processible. European Patent Publication No. 321,236 indicates that an LCP in powder form and of a certain particle size is to be mixed in a matrix resin at temperatures which will melt the matrix resin but will not deform the LCP. European Patent Publication No. 281,496 speaks of melt blending a polyester prepolymer and an LCP.
Thermochimica Acta, 137 (1988) 105-114 discusses preparing blends in the melt at 560.degree. K of VECTRA brand LCP and polybutylene terephthalate. F. P. La Manta show extrusion of blends of VECTRA polymer and nylon 6 at temperatures of 260.degree. C. and 290.degree. C.
It has been found that melt blending of a flexible matrix polymer and an LCP under such conditions in a single step can lead to undesired inhomogeneity for the resulting blend. Therefore, there is a need for improvements in the manner in which a matrix resin and a thermotropic liquid crystal polymer can be blended.